His now well-known book, Kashf-e Asrar (Discovery of Secrets) was a point by point refutation of Asrar-e Hezar Saleh (Secrets of a Thousand Years), a tract written by a disciple of Iran's leading anti-clerical historian, Ahmad Kasravi.
Also he went from Qom to Tehran to listen to Ayatollah Hassan Modarres —the leader of the opposition majority in Iran's parliament during 1920s.
Imam Khomeini became a Marja in 1963, following the death of Grand Ayatollah Seyyed Hossein Borujerdi.
In this time he could represent his religious-political ideas openly. Because the deaths of the leading, although quiescent, Shia religious leader, Ayatollah Seyyed Mohammad Borujerdi (1961), and of the activist cleric Ayatollah Abol-Ghasem Kashani (1962) left the arena of leadership open to Imam Khomeini, who had attained a prominent religious standing by the age of 60.
In addition, although ever since the rise of Reza Shah Pahlavi to power in the 1920s the clerical class had been on the defensive because of his secular and anticlerical policies and those of his son, Mohammad Reza Shah, these policies reached their peak in the early 1960s with "White Revolution."
Imam Khomeini first became politically active in 1962.
When the White Revolution proclaimed by the Shah's government in Iran called for land reform, nationalization of the forests, the sale of state-owned enterprises to private interests, electoral changes to enfranchise women, profit sharing in industry, and an anti-illiteracy campaign in the nation's schools. Most of these initiatives were regarded as dangerous, Westernizing trends by traditionalists, especially the powerful and privileged religious scholars (Ulama) who felt keenly threatened.
The Ulama instigated anti-government riots throughout the country. They found the White Revolution a sustainable ideological framework to support a particular relation of domination, in this case the monarchy of Mohammad Reza Shah Pahlavi.